I suggest to save for:
- a good armor, helm and shield (the worn dragon stuff have the best price/value ratio)
- good glasses (enchanted lenses or better)
- the great sword (great powerup!)
- the compound boots (or better)
- the simple wristwatch (or better)
- the quartz sense stone (or better)
- the steel ring
With the above set you can do all the levels (free and subscription alike). At least, I could – even with a worse armor and shield…
If you can afford, it’s useful to buy the ring of speed and probably the precious (=invisibility).
For more details, here is the full list of items
Cheers
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